1. Field of the Invention
The present invention relates to a method of manufacturing an active matrix type liquid crystal display device, and more particularly to a method of manufacturing a thin film transistor-liquid crystal display device used for a switching element.
2. Description of the Related Art
In general, an active matrix type-liquid crystal display (AM-LCD) device is thin, so that it is often used in various display devices. In this AM-LCD device, one TFT is provided as a switching element for each pixel, so that individual pixel electrodes are independently driven. The contrast is therefore not reduced based upon the reduction of a duty ratio, and also the angle of visibility is not reduced, even when the capacity of display is increased to increase the number of lines.
For fabricating a prior art TFT-LCD, a seven-mask process is required. The seven masks are a first mask for patterning a gate electrode, a second mask for patterning an etch stopper, a third mask for patterning a channel layer, a fourth mask for patterning a pixel electrode, a fifth mask for forming a pad, a sixth mask for patterning source and drain electrodes, and a seventh mask for forming a passivation layer in a TFT region.
However, there is a problem that the seven-mask process is complex, and high in view of cost. Furthermore, damages due to the mask processes occur, thereby deteriorating reliability and yield.
On the other hand, although a method of manufacturing a TFT-LCD using a five-mask process is suggested, the above problems are completely not solved.